The db holds everything, if it wasn't vacuumed, you can find the messages with active and deleted flags as well. If it was vacuumed, the deleted are gone forever, so try finding at sector level the previous versions of the threads_db2 database as well.
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The db holds everything, if it wasn't vacuumed, you can find the messages with active and deleted flags as well. If it was vacuumed, the deleted are gone forever, so try finding at sector level the previous versions of the threads_db2 database as well.

i did not find deleted msg's in the facebook db !!
and when i try to make a dd image it's encrypted i dont know why !! i already have the phone pin code and it's already rooted !! why the image is encrypted ??

i did not find deleted msg's in the facebook db !!
and when i try to make a dd image it's encrypted i dont know why !! i already have the phone pin code and it's already rooted !! why the image is encrypted ??

is this happen because userdata Partition not mounted !!

the userdata in encrypted !! i try to mount it by
mount -o rw /dev/block/mmcblk0pXX /data/local/tmp/qan
it's gives no error but when i go to /data/local/tmp/qan it's empty !!

You dumped /dev/block/mmcblk0 so it's normal that it contain encrypted stuff. Since you mentioned that you have root on that Redmi 4, try dumping /dev/block/dm-0 as well (while the phone is fully booted into Andriod) and you'll have a decrypted userdata partition image to work on.